Suture passing is utilized in the repair of soft tissue defects. A suture is typically attached to either free needles or uni-directional suture passing instruments (instruments that pass suture through tissue in only one direction) for use in surgery.
A bi-directional suture passing instrument, one which can pass suture through tissue in a forward direction (away from the user), and in a rearward direction (toward the user), can have several advantages over uni-directional suture passing instruments. Many uni-directional suture passers require an additional step to manually retrieve and pass the suture in a reverse direction, thus increasing the complexity of the surgical technique and procedural time. Some uni-directional suture passer designs allow for instrumented retrieval and reloading of the suture; however these designs require that the tissue be flexible enough that it can be lifted to expose both a first and second side of the tissue to the distal end of the instrument in order to pass the suture in a reverse direction and also require an additional step to reload the suture. A bi-directional suture passing instrument eliminates the manual retrieval step, decreases the complexity of the surgical technique and the procedural time, enhances the variety of stitch configurations that can be utilized, and increases the number of bodily tissues that can be surgically repaired.
Some bi-directional suture passer designs known in the art require that a tissue defect is approached generally parallel to the tissue, which is difficult for many surgical procedures such as disc annulus repair, due to the surgical approach to the disc space. Thus, a bi-directional suture passing instrument that approaches the tissue defect generally perpendicularly could be used in additional procedural situations in which a parallel approach bi-directional suture passing instrument is inappropriate.
Yet other bi-directional suture passer designs require that a sharp needle tip be passed through tissue in both directions. This needle passing is visible in one direction and blind in the other direction, which may result in surgical complications when working in areas adjacent to nerve roots, blood vessels, bowel, or other sensitive anatomy. A bi-directional suture passing instrument that enables a sharp needle to be visible every time it is passed through tissue, thereby increasing surgical safety when operating in the areas of sensitive anatomy would be advantageous.
Furthermore, current bi-directional suture passer designs do not effectively detachably couple the suture to the needle. Thus, features for detachably coupling the suture to the needle to improve the efficiency of the instrument are also desirable.